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15291. TGAS Cepheids and RR Lyrae stars
ID:
ivo://CDS.VizieR/J/A+A/605/A79
Title:
TGAS Cepheids and RR Lyrae stars
Short Name:
J/A+A/605/A79
Date:
21 Oct 2021
Publisher:
CDS
Description:
Parallaxes for 331 classical Cepheids, 31 Type II Cepheids and 364 RR Lyrae stars in common between Gaia and the Hipparcos and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). In order to test these first parallax measurements of the primary standard candles of the cosmological distance ladder, that involve astrometry collected by Gaia during the initial 14 months of science operation, we compared them with literature estimates and derived new period-luminosity (PL), period-Wesenheit (PW) relations for classical and Type II Cepheids and infrared PL, PL-metallicity (PLZ) and optical luminosity-metallicity (MV-[Fe/H]) relations for the RR Lyrae stars, with zero points based on TGAS. The new relations were computed using multi-band (V, I, J, Ks, W1) photometry and spectroscopic metal abundances available in the literature, and applying three alternative approaches: (i) by linear least squares fitting the absolute magnitudes inferred from direct transformation of the TGAS parallaxes, (ii) by adopting astrometric-based luminosities, and (iii) using a Bayesian fitting approach. TGAS parallaxes bring a significant added value to the previous Hipparcos estimates. The relations presented in this paper represent first Gaia-calibrated relations and form a "work-in-progress" milestone report in the wait for Gaia-only parallaxes of which a first solution will become available with Gaia's Data Release 2 (DR2) in 2018.
15292. TGAS distances
ID:
ivo://CDS.VizieR/J/MNRAS/478/3809
Title:
TGAS distances
Short Name:
J/MNRAS/478/3809
Date:
10 Dec 2021 00:51:19
Publisher:
CDS
Description:
We derive unbiased distance estimates for the Gaia-TGAS data set by correcting for the bias due to the distance dependence of the selection function, which we measure directly from the data. From these distances and proper motions, we estimate the vertical and azimuthal velocities, W and V_{phi}_, and angular momentum L_z_ for stars in the Galactic centre and anticentre directions. The resulting mean vertical motion W^-^ hows a linear increase with both V_{phi}_ and L_z_ at 10{sigma} significance. Such a trend is expected from and consistent with the known Galactic warp. This signal extends to stars with guiding centre radii R_g_<R_0_, placing the onset of the warp at R<=7kpc. At equally high significance, we detect a previously unknown wave-like pattern of W^-^ over guiding centre R_g_ with an amplitude ~1km/s and a wavelength ~2.5kpc. This pattern is present in both the centre and anticentre directions, consistent with a winding (corrugated) warp or bending wave, likely related to known features in the outer disc (TriAnd and Monoceros overdensities), and may be caused by the interaction with the Sgr dwarf galaxy ~1Gyr ago. The only significant deviation from this simple fit is a stream-like feature near R_g_~9kpc (|L_z_|~2150kpc.km/s).
15293. TGAS stars membership in 128 open clusters
ID:
ivo://CDS.VizieR/J/A+A/615/A49
Title:
TGAS stars membership in 128 open clusters
Short Name:
J/A+A/615/A49
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Tycho-Gaia Astrometric Solution (TGAS) subset of the first Gaia catalogue contains an unprecedented sample of proper motions and parallaxes for two million stars brighter than G~12 mag. We take advantage of the full astrometric solution available for those stars to identify the members of known open clusters and compute mean cluster parameters using either TGAS or UCAC4 proper motions, and TGAS parallaxes. We apply an unsupervised membership assignment procedure to select high probability cluster members, we use a Bayesian/MCMC technique to fit stellar isochrones to the observed 2MASS JHK magnitudes of the member stars and derive cluster parameters (age, metallicity, extinction, distance modulus), and we combine TGAS data with spectroscopic radial velocities to compute full Galactic orbits. We obtain mean astrometric parameters (proper motions and parallaxes) for 128 clusters closer than about 2kpc, and cluster parameters from isochrone fitting for 26 of them located inside 1kpc from us. We show the orbital parameters obtained from integrating 36 orbits in a Galactic potential.
15294. TGU 619 stars spectral types and distances
ID:
ivo://CDS.VizieR/J/BaltA/20/317
Title:
TGU 619 stars spectral types and distances
Short Name:
J/BaltA/20/317
Date:
21 Oct 2021
Publisher:
CDS
Description:
Interstellar extinction is investigated in a 1.5 square degree area of the Cepheus Flare in the direction of the dark cloud TGU 619 at l=102.5{deg}, b=+15.5{deg} . The study is based on photometric classification of 658 stars in spectral and luminosity classes down to V=16mag using photometry in the Vilnius seven-color system published in Paper I (2009BaltA..18..161Z, Cat. J/BaltA/18/161). The extinction in the investigated area is very uneven: in the most transparent directions we find an extinction of 0.3-1.1mag while in the darkest directions the maximum extinction observed is 2.6mag. The real extinction should be considerably larger since in the direction of some cloud clumps no stars are seen. The distribution of stars in the AV vs. d plot gives evidence that the dust clouds are located at a distance of 286+/-20pc.
15295. TGU 619 Vilnius photometry
ID:
ivo://CDS.VizieR/J/BaltA/18/161
Title:
TGU 619 Vilnius photometry
Short Name:
J/BaltA/18/161
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog contains magnitudes and color indices of 1304 stars down to ~16.6mag in V measured in the seven-color Vilnius photometric system in the area of 1.5 square degrees with the center at Galactic coordinates 102.4{deg}, +15.5{deg}, containing the dark cloud TGU619 in the Cepheus Flare. For most of the stars spectral and luminosity classes determined from the photometric data are given.
15296. 7th Catalog of Galactic Wolf-Rayet stars
ID:
ivo://CDS.VizieR/III/215
Title:
7th Catalog of Galactic Wolf-Rayet stars
Short Name:
III/215
Date:
21 Oct 2021
Publisher:
CDS
Description:
The VIIth catalogue of galactic Population I Wolf Rayet stars provides improved coordinates, spectral types and bv photometry of known WR stars and adds 71 new WR stars to the previous WR catalogue. This census of galactic WR stars reaches 227 stars, comprising 127 WN stars, 87 WC stars, 10 WN/WC stars and 3 WO stars. This includes 15 WNL and 11 WCL stars within 30 pc of the Galactic Center. We compile and discuss WR spectral classification, variability, periodicity, binarity, terminal wind velocities, correlation with open clusters and OB associations, and correlation with H I bubbles, H II regions and ring nebulae. Intrinsic colours and absolute visual magnitudes per subtype are re-assessed for a re-determination of optical photometric distances and galactic distribution of WR stars. In the solar neighbourhood we find projected on the galactic plane a surface density of 3.3 WR stars per kpc^2^, with a WC/WN number ratio of 1.5, and a WR binary frequency (including probable binaries) of 39%. The galactocentric distance (R_WR_) distribution per subtype shows R_WR_ increasing with decreasing WR subtype, both for the WN and WC subtypes. This R_WR_ distribution allows for the possibility of WNE->WCE and WNL->WCL subtype evolution. The successive catalogues of galactic WR stars are: I 55 stars Campbell, 1884 Astronomy and Astrophysics 13, 448 (Northfield, Minn: Goodsell Observatory) II 108 stars Fleming, 1912 Harvard College Obs. Ann. 56, 165 III 92 stars Payne, 1930 The Stars of High Luminosity, Harvard Obs. Monographs No. 3, p. 19 IV 123 stars Roberts, 1962AJ.....67...79R V 127 stars Smith, 1968MNRAS.138..109S VI 157 stars van der Hucht et al., 1981SSRv...28..227V VII 227 stars van der Hucht, 2001NewAR..45..135V, this paper
15297. 4th Catalog of Orbits of Visual Binaries
ID:
ivo://CDS.VizieR/V/39
Title:
4th Catalog of Orbits of Visual Binaries
Short Name:
V/39
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Finsen-Worley Catalog (1970), supplemented by all subsequently published orbits known to Worley and Heintz as of 1 July 1982 formed the basis for the present compilation. Practically all stars having visual orbits were reobserved in the preceding decade, often repeatedly either with micrometers or with speckle interferometers. Astrometric solutions are included but only if they were judged to be relatively certain. Orbits with period greater than 4000 years and hyperbolic orbits were rejected as being unreliable. The catalog contains 928 orbits of 847 systems (counting triples as two systems). There are 23 orbits of unresolved systems. The catalog contains for each system the names of the star and the components involved, the 1900 position, the ADS number, the magnitude and spectral type for each component, the orbital elements, the equinox of the node, the quality of the orbit, the date of the last observation, the inclusive dates for which an ephemeris is given by the author, the computer of the orbit, and a reference.
15298. 15th Complementary Catalog of SBs
ID:
ivo://CDS.VizieR/V/60
Title:
15th Complementary Catalog of SBs
Short Name:
V/60
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains the orbits and the derived masses of 436 spectroscopic binaries for which articles were published between 1982 and 1986. The magnitudes and spectral types are from the Centre de Donnees astronomiques de Strasbourg. The notes are not included in this electronic version.
15299. The abundance of boron in diffuse clouds
ID:
ivo://CDS.VizieR/J/ApJ/728/70
Title:
The abundance of boron in diffuse clouds
Short Name:
J/ApJ/728/70
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a comprehensive survey of boron abundances in diffuse interstellar clouds from observations made with the Space Telescope Imaging Spectrograph (STIS) of the Hubble Space Telescope. Our sample of 56 Galactic sight lines is the result of a complete search of archival STIS data for the BII{lambda}1362 resonance line, with each detection confirmed by the presence of absorption from OI{lambda}1355, CuII{lambda}1358, and GaII{lambda}1414 (when available) at the same velocity. Five previous measurements of interstellar BII from Goddard High Resolution Spectrograph (GHRS) observations are incorporated in our analysis, yielding a combined sample that more than quadruples the number of sight lines with significant boron detections. Our survey also constitutes the first extensive analysis of interstellar gallium from STIS spectra and expands on previously published results for oxygen and copper. The observations probe both high- and low-density diffuse environments, allowing the density-dependent effects of interstellar depletion to be clearly identified in the gas-phase abundance data for each element.
15300. The AC 2000.2 Catalogue
ID:
ivo://CDS.VizieR/I/275
Title:
The AC 2000.2 Catalogue
Short Name:
I/275
Date:
21 Oct 2021
Publisher:
CDS
Description:
The AC 2000.2 is a revised version of the 1997 release of the AC 2000 (Cat. <I/247>). It was decided that the availability of an improved reference catalogue and the inclusion of photometry from the Tycho-2 catalogue would be sufficient to warrant a complete re-reduction of the data and a new distribution of the catalogue. The AC 2000.2 catalog contains positions of 4,621,751 stars at the average epoch of plate exposures for each star (average 1907).

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